 Rod Ratios, Type 4 |
|
|
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
|
  |
| r_towle |
 Jan 2 2007, 11:47 AM
Post
#1
|
|
Custom Member  Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States 
 |
Hi, I searched (Phrase rod and ratio) and got over 1000 hits...
I think search just does not work right...I cant figure it out... Anyways... What is the optimum rod ratio for a type 4. I would like to hear lots of opinions on this one. Rich |
   |
 
|
| smontanaro |
Jan 2 2007, 12:27 PM
Post
#2
|
|
Senior Member Group: Members Posts: 1,190 Joined: 3-June 05 From: Evanston, IL Member No.: 4,197 Region Association: Upper MidWest |
Try
+rod +ratio Skip |
|
|
|
| jd74914 |
Jan 2 2007, 12:35 PM
Post
#3
|
|
Its alive Group: Members Posts: 4,841 Joined: 16-February 04 From: CT Member No.: 1,659 Region Association: North East States |
According to BrettW in this thread the optimal type IV ratio is 1.70 to 1.80.
http://www.914world.com/bbs2/index.php?sho...c=4964&st=0 |
|
|
|
| jd74914 |
Jan 2 2007, 12:41 PM
Post
#4
|
|
Its alive Group: Members Posts: 4,841 Joined: 16-February 04 From: CT Member No.: 1,659 Region Association: North East States |
Hmm . . . this graph migh interest you, as well as the article I bookmarked it in a while ago. (IMG:style_emoticons/default/smile.gif)
http://www.e30m3performance.com/tech_artic...ratio/index.htm (IMG:http://www.e30m3performance.com/tech_articles/engine-tech/rod-ratio/accel-1.gif) |
|
|
|
| Twystd1 |
Jan 2 2007, 01:18 PM
Post
#5
|
|
You don't want to know... really..... Group: Members Posts: 2,515 Joined: 12-September 04 From: Newport Beach, California Member No.: 2,743 |
What are you looking for as far as HP / TQ..????
And at what RPM will this engine be living in most of the time? Clayton |
|
|
|
| Jake Raby |
Jan 2 2007, 10:05 PM
Post
#6
|
|
Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Optimum rod ratio is dictated by the RPM range goal for the engine as well as the cam and head work as well as the longevity goal...
For engines I design I shoot for 1.75:1 for street engines, but I have some powerful combos that run as little as 1.55:1. Our race engines that sustain RPM use 2:1 or more There is no perfect rod ratio for the engine. "Its all in the combo". as always. |
|
|
|
| Borderline |
Jan 3 2007, 12:39 AM
Post
#7
|
|
Senior Member Group: Members Posts: 720 Joined: 8-February 05 From: San Juan Bautista, CA Member No.: 3,577 Region Association: Northern California |
Dema Elgin (local SF Bay area cam grinder) has an interesting article on engine design including rod ratios. lElgin Cams
|
|
|
|
|
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 23rd April 2025 - 03:15 AM |
Invision Power Board
v9.1.4 © 2025 IPS, Inc.